公开(公告)号：US06399462B1

公开(公告)日：2002-06-04

申请号：US08885046

申请日：1997-06-30

Applicant: Krishnaswamy Ramkumar ,  Sang S. Kim ,  Sharmin Sadoughi ,  Pamela Trammel ,  Avner Shelem

Inventor： Krishnaswamy Ramkumar ,  Sang S. Kim ,  Sharmin Sadoughi ,  Pamela Trammel ,  Avner Shelem

IPC: H01L2176

CPC classification number: H01L21/7621

Abstract: A method of forming a field oxide or isolation region in a semiconductor die. A nitride layer (over an oxide layer disposed over a substrate) is patterned and subsequently etched so that the nitride layer has a nearly vertical sidewall. The oxide layer and the substrate in the isolation region are etched to form a recess in the substrate having a sloped surface with respect to the nearly vertical sidewall of the nitride layer. A field oxide is then grown in the recess using a high pressure, dry oxidizing atmosphere. The sloped sidewall of the substrate effectively moves the face of the exposed substrate away from the edge of the nitride layer sidewall. Compared to non-sloped techniques, the oxidation appears to start with a built-in offset from the patterned etch. This leads to a reduction of oxide encroachment and a nearly non-existent bird's beak. The desirable range of slopes for the substrate sidewall is approximately 50°-80° with respect to a nearly planar surface of the substrate in the recess.

Abstract translation: 一种在半导体管芯中形成场氧化物或隔离区域的方法。 对氮化物层（在衬底上方的氧化物层上方）进行构图并随后进行蚀刻，使得氮化物层具有几乎垂直的侧壁。 蚀刻隔离区域中的氧化物层和衬底，以在衬底中形成相对于氮化物层的几乎垂直侧壁具有倾斜表面的凹部。 然后使用高压，干燥的氧化气氛将场氧化物生长在凹陷中。 衬底的倾斜侧壁有效地将暴露的衬底的表面远离氮化物层侧壁的边缘移动。 与非倾斜技术相比，氧化似乎从图案化蚀刻的内置偏移开始。 这导致氧化物侵蚀的减少和几乎不存在的鸟的喙。 相对于凹部中的基板的几乎平坦的表面，衬底侧壁的期望的斜率范围大约为50°-80°。